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Beginning Projects
Projects for Beginners The projects listed here are designed to engage & teach folks who have minimal experience with tinkering or making things. Pick a project from the list to learn more about it! Whether the size of a tooth brush or the size of a scrub brush these "Bots" have the same basic features. A battery power source, a vibrating motor, a switch of some sort and a bristle brush. The brush bot we will build in this wiki is made with a tooth brush, a battery holder, a coin battery, a micro vibratory motor, some wire, and a brass strip with screws to create a home made switch. Because I'm concerned with the bot tipping over, and to give me a little more space to anchor the components, I am also creating a 3D printed plastic shell. How they work The vibrations from the motor's up and down vectors flex and release the bristles beneath creating a sort of "pogo stick" action. if the bristles are angled in one direction, the bouncing will move the bot forward as the individual bristles straighten out when the vector of the bounce is in the upward direction, much as the pole of a pole-vaulter pushes the vaulter forward and up over the bar. on the down stroke, the bristles are again loaded for the next spring forward. Preparing the brush If the tooth brush has straight bristles, like the one in picture (A''') (or bristles pointing in opposite directions), you will need to orient them towards the "back" of the brush bot (as in '''B). This is because if you don't, the downward vector of the motor will rend to load the bristles in a random or contradictory manner, resulting in a random movement path for the bot (C'''). Most toothbrush bristles are made of nylon and as such can be softened by heat and bent in one direction. Nylon softens form 170F to 329F and can be reshaped if deformed and held till it cools. If you go above 428F the nylon will melt and degrade potentially outgassing hazardous materials and fusing the bristles together. I recommend using boiling water (210F or so) or if you don't get satisfactory results mineral oil. If you use oil you will need to use a thermometer to carefully monitor the temperature and a face shield incase any moisture gets into the oil causing it to "pop". Whether you use water or oil you will need to protect your hands from coming into contact with the hot brush / liquids while you form the bristles. For forming the bristles I recommend leaving the tooth brush handle in place to give you a "safe" way to hold it while you shape and cool the nylon bristles. The technique I found, was just to press the bristles against a table, and bending them nearly flat as they will tend to spring back when released. When you have shaped the bristles the way you want them, it is time to cut off the brush head. Use a fine tooth saw and cut slowly as the cutting action may create enough heat to gum up the blade with plastic. Rubbing the blade with soap or wax before cutting will help. Remove burs from the cut edge and sand the back of the brush to give the gluing area a "tooth". Clean the brush head thoroughly to remove any grease or oil and then dry it. Next, apply glue to the head (and if necessary) the bot body. Use a glue that is good for plastics but is not so hot (aggressive solvents) as to melt the parts. I used "Shoe Goo", but there are a large number of other choices out there. Carefully align the brush head inside the carapace before it sets and then set it aside to harden. '''Work in progress...More to follow Blink (Arduino) This is often the first project an Arduino programmer creates; it doesn't even need any wires! TinkerCAD Tutorial This tutorial, found at www.tinkercad.com (registration required) is a great start to easy, web-based 3D modelling.